The article “Warfarin Therapy: Evolving Strategies in Anticoagulation” (February 1999, page 635) contained an error. On page 637, the third sentence of the third complete paragraph states: “Administration of loading doses has also been hypothesized to potentiate a hypocoagulable state because of severe depletion of protein C.” The sentence should have referred to a hypercoagulable state. Although warfarin is intended to produce a hypocoagulable state, loading doses of warfarin may paradoxically result in a hypercoagulable state because of significant reductions in protein C and protein S.